1. Field of the Invention
This invention relates generally to a switch assembly, more particularly, it relates to a push-button switch assembly in simple structure for control of power supply by depressing a push button to oppress or release a resilient contact piece directly so as to simplify assembling process and reduce production cost.
2. Description of the Prior Art
A power switch is a widely used electronic component for ON/OFF control of a power supply, and is highlighted in its structural complexity in consideration of cost, and particularly, of its reliability of security.
So far, a variety of patents regarding switch assembly, including U.S. Pat. No. 4,167,720, 4,937,548, 5,223,813, 5,451,729, 5,558,211, etc, has already been disclosed, however, a common defect may be assigned to too many components and too complicated interaction of the switch assembly.
As illustrated in FIG. 1, when a prior push button 502 of a push-button switch rests at a top position, a contact point 506 of a conductive piece 504 is separated from a contact point 510 of a contact pin 508; and when the push button 502 is depressed to a lower position, a spring 514 and a protruding rod 512 disposed in the push-button switch will push the conductive piece 504 forward to enable the contact point 506 to contact with the contact point 510 of the contact pin 508 to have the switch turned "ON".
However, mechanical contact of the spring 514 and the protruding rod 512 will inevitably result in elastic fatigue and poor contact in the long run, besides, the top face of the push button 502 is somewhat insufficient for design of any reminding symbol or pattern as for promoting appended value.